plugs

I am trying to get a fan to upgrade a fanless pc that overheats in summer by adding a fan. I found this picture of the motherboard, does anyone know what this 4 pin cpu fan plug type is called?

My brother has brought to my attention that many YouTube videos and websites he finds on how to crimp for a shielded CAT5e/6 cable, including the shielded cable that was crimped at his house by the ISP, show that the sleeve is not inserted into the RJ-45 plug. Example...